Feature request : Add S3 tag on uploaded backups

Proposal

The need is very simple :

• Allow to add S3 tags on uploaded backups .tar files generated with gitlab-rake gitlab:backup:create

It could be setup as below in gitlab.rb file:

gitlab_rails['backup_upload_tags'] = {'tag1':'value1','tag2':'value2'}

I don't know how to implement this in a clean way, but I saw Fog library example allowing this feature :

directory = s3.directories.new(key: 'gaudi-portal-dev')
file = directory.files.create(key: 'user/1/Gemfile', body: File.open('Gemfile'), tags: 'Org-Id=1&Service-Name=My-Service')

(https://github.com/fog/fog-aws#creating-a-file)

Thank you